Proteus syndrome with syringohydromyelia and arachnoid cyst

Introduction Proteus syndrome (PS) is a rarely seen, sporadic disorder with a wide range of abnormalities including asymmetrical overgrowth, skin lesions, dysregulated adipose tissue, and vascular malformations. Brain and spinal malformations are extremely rare; syringohydromyelia and arachnoid cyst have not been reported previously. Materials and methods We present a 5-year-old girl with PS having severe central nervous system (CNS) abnormalities demonstrated by magnetic resonance imaging (MRI) including craniocutaneous lipomatosis, hemimegalencephaly, arachnoid cyst, and syringohydromyelia. A commentary on this paper is available at doi: .